help! another pertronix question

[rca1pollock]

first time poster . have looked through old posts and still can,t figure out how to wire ignitor module to coil. i have 1984 merc 120r ser#69*******. changing to electronic ignitor 1 ignition. have it hooked up except for positive from module. my coil is a kem u12a (req.external ballast resistor) that seems to have about 2 ohms resistance with nothing attached. my battery is new and at 12.5v. voltage at pos. terminal of coil with key on and red and purple/yellow wires attached is 2v less at 10.5.(must be resistor wire inside harness before coil). when i ground neg. side of coil to battery and check voltage at + side coil it is only 4 volts. do i have to open wire harness and splice positive of module BEFORE resistor wire.. and add a 1ohm resistor between resistor wire and pos+ of coil (or just buy 3ohm coil)..is any of this correct?

 

[MikDee]

Take of the resistor wire going to the Pos+ at the coil, tape it up, and don't use it. Run a new full 12 volt ignition wire to the Pos+ side of the coil, Pertronics needs a full 12 volts to work right. The black wire coming from the Neg- side of the coil to the Distributor, is the control wire, it acts as ground to complete the whole ignition circuit, for everything to work!

 

[rca1pollock]

So after I tape or eliminate purple wire at coil I can trace that back to alternator (before resistor wire but still ignition controlled)..run new 18 guage wire straight to + coil and just hook red wire from module to + of coil also...will that damage coil or module due to coil only being 2 ohms and being 4 cylinders..I read somewhere that 4 cylinders need at least 3 ohms in coil circuit.

 

[rca1pollock]

So after I tape or eliminate purple wire at coil I can trace that back to alternator (before resistor wire but still ignition controlled)..run new 18 guage wire straight to + coil and just hook red wire from module to + of coil also...will that damage coil or module due to coil only being 2 ohms and being 4 cylinders..I read somewhere that 4 cylinders need at least 3 ohms in coil circuit.

 

[rca1pollock]

ok..i uncovered entire harness and spliced into purple ignition controlled wire that goes to choke and alternator...fed that to positive + of coil. now have full 12+ volts. hooked red wire from ignitor to + of coil also. i guess if the coil can't take that voltage i'll order a 3 ohm 40511 ignitor coil..and keep it on boat...my only other question is if i HAVE TO remove purple resistance wire that is also still on +coil side..i hate to clip it before i run the boat for awhile and make sure all is ok. thanks in advance!

 

[rca1pollock]

do i have to eliminate resistance wire? will it cause any problems still hooked up even with full 12v wire also?:cold::cold:

 

[achris]

If you want to, you can leave the resistive wire connected to the coil for safe keeping. Having the resistive wire and a 'normal' wire in parallel won't change anything, you will have full voltage at the coil...

 

[rca1pollock]

thank you achris.! i will set timing to 8 btdc today and try to run it today or sunday!